The dependency on limited sources of oil and other carbon-based energy resources may hinder future economic growth and security for many nations. To advance towards independent energy economies, nations are considering alternative energy sources such as hydrogen. Hydrogen offers a promising solution, but there is currently a lack of suitable carriers for hydrogen that have a relatively high-energy density and low cost for vehicle storage application. Transport and an onboard vehicular storage of hydrogen (H2) is a well-known bottleneck and one limiting factor in developing a hydrogen-based economy. The current lack of convenient, safe and cost effective materials and methods to store hydrogen has limited the widespread use of hydrogen as a fuel and as a mode for energy storage.
Guideline objectives published by the United States Department of Energy (USDOE) for hydrogen storage capacity for vehicle transportation have not yet been met by conventional technologies because of various size, recharge kinetics, cost and/or safety issues. One example of such conventional technologies includes the use of nanoporous metal-organic frameworks (MOFs) that enhance the adsorption of supercritical H2. This appears to be accomplished by overlapping the charged potential fields from both sides of the pore structure to enhance the interaction potential. Another example of such conventional technologies includes the use of titanium alloys as hydrogen storage solids. However, neither of these conventional technologies has proven production practical for hydrogen storage with respect to meeting or exceeding the USDOE guideline objectives.
Other attempts to achieve suitable hydrogen storage capacities involve laboratory prepared nanomaterials and composite materials. One attempt includes the use of ethylene gas to prepare carbon nanofibers having widths that vary from about 2.5 nm (nanometers) to about 1 micron and lengths from about 5 to about 100 microns, however, the reproduction of these laboratory prepared nanomaterials was not adequately controllable. The expense of creating such materials can be thousands of dollars per gram of material. Another drawback to using such conventional nanomaterials has been the difficulty in controlling their synthesis while preserving the nanoscale integrity of the subsequent assembly. Laboratory prepared materials have provided hydrogen storage capacities at near ambient conditions. However, such conventional composite materials are sometimes plagued by a lack of reproducibility and can be very expensive for larger-scale production.
Therefore, a need exists for systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies.